I think it is also telling that Mr. Weston would allow his son to be reared by the Churchills despite their feelings about the marriage. I also wonder about Mr. Weston's situation at that point. If he was still in the militia when his wife died, it might have been quite difficult for him to cope with the upbringing of a young child, and so the Churchills' offer to take young Frank may have come as a relief to him.